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A 79-year-old man presented with dilated cardiomyopathy and chronic atrial fibrillation. A DDD pacemaker was implanted due to sick sinus syndrome. His left ventricular ejection fraction was 23%. He was repeatedly admitted with congestive heart failure. Although cardiac resynchronization therapy was attempted, insertion of a pacing lead into the coronary sinus failed. Right ventricular bifocal pacing was done. The QRS width was shortened to 155 msec during bifocal pacing and 157 msec during right ventricular outflow pacing from 221 msec during right ventricular apical pacing. Heart failure was improved from New York Heart Association class III to II. Regional wall motion was assessed by strain of the myocardium. Bifocal pacing increased stroke volume due to improvement of longitudinal dyssynchrony of the septal and lateral walls. Bifocal pacing is effective for patients with severe congestive heart failure in whom biventricular pacing therapy has failed. Strain Doppler imaging is useful for the assessment of regional wall motion during cardiac pacing.  相似文献   
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Objective

The aim of this study was to compare growth factor amount contained in platelet rich fibrin (PRF) and compare with that in platelet rich plasma (PRP), and in whole blood. And also to investigate distribution of growth factors and cellular components in PRF.

Materials and Methods

PRF and PRP were obtained from the same sample of peripheral blood. Extraction of proteins were done with lysis buffer, accompanied by freeze and thaw procedures. Concentration of two representative growth factors in platelets: platelet derived growth factor (PDGF) and transforming growth factor beta (TGF-β), were measured with enzyme-linked immunosorbent assay (ELISA). PRF was cut into three parts: (top, middle and bottom), and growth factor concentration was measured respectively. Paraffin embedded section of PRF was observed with Giemsa stain. Immuno-histochemical analysis with anti-PDGF and anti-TGF-β antibodies was also conducted.

Results

The growth factor levels in PRF was higher than in peripheral blood and comparable to those in PRP. Growth factor levels in bottom part of PRF was much higher than in top and middle part. Microscopically, platelets and mono-nucleated cells were concentrated just above the yellow–red interface. Poly-nucleated cells were concentrated below the interface.

Conclusion

The growth factors were surely concentrated in PRF. This result can support basis of good clinical outcomes. For effective application of PRF, the knowledge that growth factors and cells are not equally distributed in PRF should be utilized.  相似文献   
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BackgroundIt is critical to have an accurate measurement of solid tumor size in order to predict the invasiveness of small lung adenocarcinomas. Some lesions cannot be measured accurately via High-resolution computed tomography (HRCT) due to their irregular shape and unclear borders. For this reason, we evaluated the relative efficacy of three-dimensional (3D) CT for predicting invasive adenocarcinoma.MethodsWe evaluated 195 patients with clinical stage IA adenocarcinomas, including 109 with lesions documented as invasive that were surgically resected at our institute during 2017. All lesions were categorized as either (I) lesions that were difficult to evaluate (i.e., hazy lesions; HL) or (II) more typical lesions (TL). The relationships between solid tumor size as determined by HRCT, solid tumor volume as determined by 3D CT and pathologic diagnosis were evaluated.ResultsFifty-seven patients (29%) were diagnosed with HL. We set the cut-off value for the solid volume at 225 mm3 as predictive for invasive adenocarcinoma. When evaluating all 195 patients as a group, the accuracy, sensitivity, and specificity based on the solid tumor volume were similar to those based on the solid tumor size. When we limit our analysis to the HL group, the specificity based on solid tumor volume (65.5%) was higher than that based on solid tumor size (44.8%) with a difference that approached statistical significance (P=0.070).Conclusions3D CT was equivalent to HRCT for predicting invasive adenocarcinoma and may be particularly useful for diagnosing lesions that are difficult to evaluate on HRCT.  相似文献   
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BACKGROUND Sedation is commonly performed for the endoscopic submucosal dissection(ESD) of early gastric cancer. Severe hypoxemia occasionally occurs due to the respiratory depression during sedation.AIM To establish predictive models for respiratory depression during sedation for ESD.METHODS Thirty-five adult patients undergoing sedation using propofol and pentazocine for gastric ESDs participated in this prospective observational study. Preoperatively, a portable sleep monitor and STOP questionnaires, which are the established screening tools for sleep apnea syndrome, were utilized. Respiration during sedation was assessed by a standard polysomnography technique including the pulse oximeter, nasal pressure sensor, nasal thermistor sensor, and chest and abdominal respiratory motion sensors. The apnea-hypopnea index(AHI) was obtained using a preoperative portable sleep monitor and polysomnography during ESD. A predictive model for the AHI during sedationwas developed using either the preoperative AHI or STOP questionnaire score.RESULTS All ESDs were completed successfully and without complications. Seventeen patients(49%) had a preoperative AHI greater than 5/h. The intraoperative AHI was significantly greater than the preoperative AHI(12.8 ± 7.6 events/h vs 9.35 ± 11.0 events/h, P = 0.049). Among the potential predictive variables, age, body mass index, STOP questionnaire score, and preoperative AHI were significantly correlated with AHI during sedation. Multiple linear regression analysis determined either STOP questionnaire score or preoperative AHI as independent predictors for intraoperative AHI ≥ 30/h(area under the curve [AUC]: 0.707 and 0.833, respectively) and AHI between 15 and 30/h(AUC: 0.761 and 0.778, respectively).CONCLUSION The cost-effective STOP questionnaire shows performance for predicting abnormal breathing during sedation for ESD that was equivalent to that of preoperative portable sleep monitoring.  相似文献   
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To date, almost all case reports of insulin‐derived amyloidosis described the presence of a subcutaneous mass that was observable on physical examination. This report presents two cases of insulin‐derived amyloidosis without palpable masses at insulin injection sites. In both cases, blood glucose concentrations improved, and the insulin dose could be reduced by an average of 45% after changing the insulin injection sites. The insulin absorption at the site was reduced to at most 40% of that at a normal site in one case. Magnetic resonance imaging and ultrasonography were useful to screen and differentiate insulin‐derived amyloidosis without a palpable mass. This report showed that insulin‐derived amyloidosis without a palpable mass can be present at the insulin injection site, and has similar clinical effects to insulin‐derived amyloidosis with palpable masses.  相似文献   
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